The kinetics of complex formation of hen egg lysozyme with chloranil

Abstract

1. 1. The rate of complex formation of hen egg-white lysozyme with chloranil in dimethyl-sulfoxide at different molar ratios was investigated. 2. 2. The reaction rates were studied by the “stopped-flow” method. The complex forming reactions follow kinetics of first order. A linear dependence of K obs (sec −1) with donor concentration was obtained. The formation of lysozyme-chloranil complex is similar to that for the free tryptophanchloranil complex. The complex formation reaction between lysozyme and chloranil in dimethyl-sulfoxide inactivates the enzyme activity. 3. 3. The absorption and fluorescence spectra showed that the indole side chain of tryptophan can act as an electron donor in the complex formation reaction with chloranil. 4. 4. The kinetic study with excess of chloranil, suggests that chloranil reacts first with tryptophyl residues in active site than other amino acid residues. The inhibition curve course confirmed this assumption.